. V. FATTY SUBSTANCES. 109 



On the other hand, it has been, proved, by a great num- 

 ber of physiological observations, that in animals fed on 

 fat, the chyle is more abundant and milky than usual, and 

 that these same substances may be extracted from it. More- 

 over, when submitted to the microscope, small globules of 

 fat are perceived in it. 



The experiments of Sandras and Bouchardat have proved 

 this fact, beyond doubt. These chemists fed animals with 

 oil of sweet almonds, and found this substance in the chyle ; 

 and they obtained a like result with suet. When wax was 

 employed, they found only a small quantity of this sub- 

 stance in the chyle ; but which, however, was augmented 

 when the wax was introduced in a state of solution in oil. 



These gentlemen have also examined the contents of the 

 stomach and intestines of animals fed exclusively upon 

 fat ; and they found in the stomach a large portion of 

 fat, solidifiable by cold, and contained in a very acid liquor. 

 There was, also, both in the large and small intestines, a 

 kind of thick pap (bouillie,) from which ether extracted a 

 large quantity of flit. 



It results from these facts, of the truth of which I have 

 satisfied myself, that fatty matters suffer no change in the 

 stomach, and that they pass into the intestines without 

 having undergone any modifications except being divided 

 and liquefied by the heat of this organ. Moreover, by 

 causing the gastric juice to act on fat out of the stomach, 

 no change appears to be effected in it. 



The alkali of the bile and of the pancreatic juice satu- 

 rate, in the intestines, the acid of the gastric juice. Here, 



contact vvith putrefying caseine, there is separated from the elements of 

 the sugar, if the oxygen of the air be excluded, a certain quantity of car- 

 bonic acid and of hydrogen gases, and we obtain, as is now well known, 

 a fatty or oily acid, the butyric acid.' 1 ' 1 (Liebig's Animal Chemistry, p. 

 113. 3d ed. 1846.) J. P. 



